Lesson 22: Explorations with Pi
A dog is tied to the corner of two buildings
with a leash that is 13 yards long, as shown in
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The dog is convinced that a bone is buried
somewhere in the yard, but its movement, of
course, is restricted by the length of the leash. Find
the total area of ground the dog can reach from its
leash.
Two rectangles and two sectors are arranged as shown
in )LJXUH.
Each rectangle is 2 inches by 8 inches. What is the sum of the
areas of the two sectors?
)LJXUH shows two concentric circles and a line segment of
length 7 tangent to the small circle.
If the radius of the small circle is 6, what is
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A sector is inscribed in a regular heptagon. The sides of the sector
match the sides of the heptagon. What, to one decimal place, is the
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10
10
4
6
8
13
Figure 22.11
60°
Figure 22.12
7
Figure 22.13
Figure 22.14